Safety switch having flatwise pivotable blades



March 7, 1967 w. c, CARLYLE 3,308,256

SAFETY SWITCH HAVING FLATWISE PIVOTABLE BLADES Filed Dec. 30, 1963 3 Sheets-Sheet l INVENTOR.

I 'mwammd g/e arch 7, 1967 I w. c. CARLYLE 3,308,256

SAFETY SWITCH HAVING FLATWISE PIVOTABLE BLADES Filed Dec. 30, 1963 3 Sheets-Sheet 5 isl J 9 ll g 2 1| i Q H Z5 55 f 65 110 h 35 I United States Patent 3 308,256 SAFETY SWITCH HAVIN G FLATWISE PIVOTABLE BLADES William C. Carlyle, Toronto, Ontario, Canada, assignor to Square D Company, Park Ridge, Ill., a corporation of Michigan Filed Dec. 30, 1963, Ser. No. 334,222 4 Claims. (Cl. 200-114) This invention relates generally to fusible safety switches, and more particularly to improved mounting structure and operating mechanism for a switch blade.

An object of the invention is to provide improved mounting structure and operating mechanism for a switch blade of a fusible safety switch.

Another object is to provide a safety switch including a generally flat substantially rigid one-piece elongated switch blade mounted for flatwise pivotal movement by means including a generally spherical bearing surface on a side of the switch blade adjacent one end, the switch blade carrying a movable contact adjacent its other end for butt-type engagement with a stationary contact.

A further object is to provide a safety switch including a generally flat elongated switch blade mounted for flatwise pivotal movement and an operating handle operatively connected thereto and mounted for pivotal movement about an axis generally perpendicular to the axis of pivotal movement of the switch blade,

A still further object is to provide a safety switch including a generally flat elongated switch blade mounted for flatwise pivotal movement and an elongated blade actuator operatively connected thereto and mounted for reciprocal movement longitudinally of the actuator in a path generally perpendicular to the axis of pivotal movement of the switch blade.

Yet another object is to provide a safety switch including a generally flat elongated switch blade mounted for flatwise pivotal movement,-an elongated blade actuator operatively connected to the switch blade and mounted for reciprocal movement longitudinally of the actuator in a path generally perpendicular to the axis of pivotal movement of the switch blade, a cam operatively connected to the blade actuator by a lost-motion connection and mounted for pivotal movement about an axis generally perpendicular to the axis of flatwise pivotal movement of the switch blade, an operating handle operatively connected to the cam by a lost-motion connection, an overcenter spring operatively connected to the cam, and spring detent means holding the blade actuator and switch blade in closed position until the cam passes over center in the switch opening direction.

' Another object is to provide a fusible safety switch including a combination fuse clip and switch blade mounting, and a generally flat elongated switch blade mounted adjacent one of its ends on the combination fuse clip and switch blade mounting for flatwise pivotal movement.

These and other objects will appear when the following specification is considered along with the accompanydrawings in which:

FIG. 1 is a reduced perspective View of a safety switch constructed in accordance with the invention, with the cover closed and the operating handle in the off position;

0 ice FIG. 2 is a fragmentary view of the switch of FIG. 1 from the side thereof adjacent the operating handle, the operating handle being shown in the on position and portions of the box and operating handle being broken away;

FIG. 3 is a view similar to FIG. 2, but with the operating handle in the off position;

FIG. 4 is an exploded perspective view of certain parts of the operating mechanism of the switch of FIG. 1;

FIG. 5 is a fragmentary front view of the switch of FIG. 1, the cover being removed and the switch being shown in open position;

FIG. 6 is a view similar to FIG. 5, but with the switch in closed position;

FIG. 7 is a sectional view of the switch of FIG. 1 taken generally along the line 77 of FIG. 6;

FIG. 8 is a fragmentary sectional view of the switch of FIG. 1 taken generally along the line 8-8 of FIG. 6;

FIG. 9 is a fragmentary sectional view taken generally along the line 9-9 of FIG. 5; and

FIG. 10 is a fragmentary sectional view taken generally along the line 1010 of FIG. 6.

FIG. 1 shows a safety switch 12 constructed in accordance with the invention and including an open front box 14, a front cover 16, and an operating handle 18.

As shown in FIGS. 5 and 9, a molded insulating base 20 is secured to a back wall portion 22 of the box 14 by means of a screw 26 threaded therein and a pair of tangs 24 formed integrally with the back wall portion 22. A pair of generally L-shaped terminal straps 28 are secured to the base 20 by a pair of screws 30 threaded respectively thereinto from the rear of the base 20, as shown in FIGS. 5, 6, and 7. One leg portion of each terminal strap 28 includes a tongue portion 32 extending through and securing an electrical connector or line terminal 34 to the base 20. The other leg portion of each terminal strap 28 has a stationary contact 36 mounted thereon.

A pair of combination fuse clips and switch blade mountings are secured to the base 20 by a pair of screws 38, as shown in FIGS. 5, 6, and 8. The screws 38 extend respectively through a pair of generally U-shaped resilient members 40 and are threaded respectively into a pair of generally L-shaped rigid members 42 from the rear of the base 20. The members 42 are provided respectively with boss portions 44 which are received respectively in corresponding openings in the =bight portions of the U-shaped members 40. Formed leg portions 46 of members 42 cooperate on one side respectively with formed leg portions 48 of resilient members 40 to pro- -vide fuse clips and cooperate on the other side respectively with formed leg portions 50 of resilient members 40 to provide mountings for a pair of switch blades 52. As shown in FIG. 8, the leg portions 46 are provided respectively with holes 54 the peripheral edges of which provide seats for the switch blades 52. The leg portions 5-0 and the switch blades 52 are dimpled or bulged to form rounded projections or generally spherical bearing surfaces seating respectively in the leg portions 46 at the holes 54. The switch blades 52 are held respectively between the rigid leg portions 46 and resilient leg portions 50 and are thus provided respectively with generally spherical bearing type mountings which enable them to be pivoted fiatwise from the open position thereof shown 3 in FIG. 5 to the closed position thereof shown in FIG. 6 and vice-versa.

Opposite their mounted ends the blades 52 are provided respectively with movable contacts 56 for cooperation with the stationary contacts 36. The blades are pivoted fiatwise between open and closed positions by a blade actuator 58 made of insulating material and slidably mounted in portions of the molded base 20. The blade actuator 58 is shown in perspective in FIG. 4. A forked cam follower 60 is rivetted or otherwise secured to one end of the blade actuator 58. The switch blades 52 extend respectively through a pair of apertures 62 in the blade actuator, and a pair of compression springs 64 are mounted respectively in the apertures 62 on the opposite sides of the blades 52 from the movable contacts 56.

The forked cam follower 60 has a lost-motion connection with a thread-like projection 65 of a cam 66 pivotally mounted at one end in the base 20 and at the other end in a side wall portion 68 of the box 1 4.

The handle 18 includes a disc portion 70 pivotally mounted on the end of the cam 66 adjacent the side wall portion 68 and having a tab 72 (FIGS. 2-4) extending into a recess 74 of the cam to provide a lostmotion connection therebetween. An overcenter spring 7 6 is connected at one end to the base 20 and at the other end to the cam 66. The pivotal movement of the cam 66 and handle 18 in opposite directions is limited by engagement of a pair of stop surfaces 78 and 80 respectively with a tab 82 offset inwardly from the side wall portion 68 of the box 14.

A spring detent is provided for the blade actuator 58 to hold the switch blades 52 closed until the cam 66 and handle 18 pass over center in the switch opening direction. As shown in FIG. 10, a generally flat spring 84 is carried in a recess 86- in the blade actuator 58 for sliding movement therewith in the base 20, the interior of which is provided with a projection 88 for cooperation with a rounded projection 90 of the springs 84-.

As shown in FIGS. 5 and 9, a pair of screws 92 threaded respectively into a pair of terminal straps 94 from the rear of the base 20' secures a pair of fuse clips 96 thereto in alignment with the fuse clips provided by the leg portions 46 and 48 of the members 42 and 40. The terminal straps 94 include projecting tongue portions 98 which respectively hold a pair of electrical connectors or load terminals 100 on the base 20. A generally E-shaped neutral wire connector .102 provided with three electrical connectors 104 is secured to the base 20 by a screw 106.

A pair of hinges 108 (FIGS. 5 and 7) formed integrally with a side wall portion 110 of the box 14 are provided for hinging the cover 16 to the box.

It will be seen that an improved switch operating mechanism has been provided in which movement of the operating handle parallel to the adjacent side wall of the box moves the blade actuator perpendicularly to the side wall of the box and pivots the switch blades flatwise to move the movable contacts into butt-type engagement with the stationary contacts.

Various modifications may be made in the structure shown and described without departing from the spirit and scope of the invention as set forth in the appended claims.

I claim:

1. A safety switch comprising a box including a back wall portion and a side wall portion, an insulating base in said box secured to said back wall portion, a stationary contact mounted on said base, a generally that substantially rigid one-piece elongated switch blade pivotally mounted adjacent one end on said base for flatwise pivotal movement about an axis generally perpendicular to said back wall portion of said box and carrying a movable contact adjacent its other end, the movable contact engaging said stationary contact in butt-type engagement upon flatwise pivotal movement of the switch blade, a blade actuator recip'roc-ably mounted on said base for reciprocal movement generally perpendicular to said side wall portion of said box, means connecting said blade ac tuator and switch blade in a manner such that movement of said blade actuator causes movement of said switch blade, a cam pivotably mounted for pivotal movement about an axis generally perpendicular to said side wall portion of said box, means connecting said cam and blade actuator in a manner such that movement of said cam causes movement of said blade actuator, an operating handle pivotably mounted for pivotal movement about an axis generally perpendicular to said side wall pontion of said box, and means connecting said handle and cam in a manner such that movement of said handle causes movement of said cam.

2. A safety switch as claimed in claim 1, wherein one end portion of said cam is mounted on said base and the other end portion of said cam is mounted on said side wall portion of said box.

3. A safety switch comprising a box including a back wall portion and a pair of opposed side wall portions, an insulating base in said box secured to said back wall portion, a stationary contact mounted on said base, a generally flat elongated switch blade pivotably mounted adjacent one end on said base for flatwise pivotal movement about an axis generally perpendicular to said back wall portion of said box and carrying a movable contact on one side thereof and adjacent its other end the movable contact engaging said stationary contact upon flatwise pivotal movement of the switch blade, a blade actuator reciprocably mounted on said base for reciprocal movement generally perpendicular to said side Wall portions of said box, means connecting said blade actuator and switch blade in a manner such that movement of said blade actuator causes movement of said switch blade, a compression spring carried by said blade actuator in engagement with the other side of said switch blade from said movable contact and compressed by said blade actuator after engagement of said movable contact with said stationary contact to establish pressure between said contacts, a cam pivotably mounted for pivotal movement about an axis generally perpendicular to said side wall portions of said box, means connecting said cam and blade actuator in a manner such that movement of said cam causes movement of said blade actuator, an operating handle movably mounted adjacent one of said side wall portions for movement generally parallel to said side wall portions of said box, means connecting said handle and cam in a manner such that movement of said handle causes movement of said cam, an overcenter spring, means connecting said overcenter spring and cam in a manner such that movement of said overcenter spring causes movement of said cam, and spring detent means holding said blade actuator and switch blade in closed position until said cam passes over center in the switch opening direction.

4. A fusible safety switch comprising a stationary contact, a generally flat elongated switch blade pivotably mounted adjacent one end for fiatwise pivotal movement and carrying a movable contact adjacent its other end, the movable contact engaging said stationary contact in butt-type engagement upon flatwise pivotal movement of the switch blade, and a combination fuse clip and switch blade mounting including a generally U-shaped resilient first member and a generally L-shaped rigid second member having one leg portion secured to the bight portion of said first member and the other leg portion extending between and aligned with the leg portions of said first member, one leg portion of said first member and said other leg portion of said second member including means for receiving one end of a. cartridge fuse on one side of said other leg portion of;

blade on the other side of said other leg portion of 5 said second member.

References Cited by the Examiner UNITED STATES PATENTS 10/ 1950 Daly 200-144 X Koening 200l53 X Savage 200166 McFarland 2006 Miller 200-414 D'ahlgren 2006 Cellerini et a1. 200--1 14 Williams 200166 BERNARD A. GILHEANY, Primary Examiner.

11/ 1917 Simon 200-3 10 H. A. LEWITTER, Assistant Examiner. 

1. A SAFETY SWITCH COMPRISING A BOX INCLUDING A BACK WALL PORTION AND A SIDE WALL PORTION, AN INSULATING BASE IN SAID BOX SECURED TO SAID BACK WALL PORTION, A STATIONARY CONTACT MOUNTED ON SAID BASE, A GENERALLY FLAT SUBSTANTIALLY RIGID ONE-PIECE ELONGATE D SWITCH BLADE PIVOTALLY MOUNTED ADJACENT ONE END ON SAID BASE FOR FLATWISE PIVOTAL MOVEMENT ABOUT AN AXIS GENERALLY PERPENDICULAR TO SAID BACK WALL PORTION OF SAID BOX AND CARRYING A MOVABLE CONTACT ADJACENT ITS OTHER END, THE MOVABLE CONTACT ENGAGING SAID STATIONARY CONTACT IN BUTT-TYPE ENGAGEMENT UPON FLATWISE PIVOTAL MOVEMENT OF THE SWITCH BLADE, A BLADE ACTUATOR RECIPROCABLY MOUNTED ON SAID BASE FOR RECIPROCAL MOVEMENT GENERALLY PERPENDICULAR TO SAID SIDE WALL PORTION OF SAID BOX, MEANS CONNECTING SAID BLADE ACTUATOR AND SWITCH BLADE IN A MANNER SUCH THAT MOVEMENT OF SAID BLADE ACTUATOR CAUSES MOVEMENT OF SAID SWITCH BLADE, A CAM PIVOTABLY MOUNTED FOR PIVOTAL MOVEMENT ABOUT AN AXIS GENERALLY PERPENDICULAR TO SAID SIDE WALL PORTION OF SAID BOX, MEANS CONNECTING SAID CAM AND BLADE ACTUATOR IN A MANNER SUCH THAT MOVEMENT OF SAID CAM CAUSES MOVEMENT OF SAID BLADE ACTUATOR, AN OPERATING HANDLE PIVOTABLY MOUNTED FOR PIVOTAL MOVEMENT ABOUT AN AXIS GENERALLY PERPENDICULAR TO SAID SIDE WALL PORTION OF SAID BOX, AND MEANS CONNECTING SAID HANDLE AND CAM IN A MANNER SUCH THAT MOVEMENT OF SAID HANDLE CAUSES MOVEMENT OF SAID CAM. 